@fma said in User-Defined Macros in 2 columns ?:
BTW, on DWC, could it be possible to let the folder open once the macro is clicked? For now, the folder automatically closes, which is annoying when I want to launch several macros from this folder...
Your idea is better, instead of making it a menu, it should be a section to expand, and stay open until you click on another section, and have that one stay open.
Maybe even open when you hover the mouse on top of it, this way you don't need 2 clicks

Highly unlikely.
DWC is a web application and should be restricted by your browser.
I don't see anything in the DWC source code that would try to open a usb or com port (most browsers don't even support this).
Maybe you have an IP address conflict or some other tools trying to make connections to the same port?

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